Steam enough broccoli and cauliflower to fit in casserole pan.
While that's steaming, on med-low melt, margarine in medium-sized pot. Mix in flour. When this mixture begins to bubble add in garlic, tamari, water, and turmeric. When it begins to thicken and bubble, add nutritional yeast and oil. Gradually add in soymilk-all of this makes a "cheese" sauce and the more soymilk that's added, the creamier it'll be.
While everything's warm, put the veggies in the casserole pan, sprinkle salt and pepper on 'em, pour the sauce on top and mix thoroughly. Sprinkle on some red pepper if you want.
Top with breadcrumbs and bake on 350 degrees Fahrenheit for 10-15 minutes.
Mmmm, mmmm

SO HOW'D IT GO?

This casserole has tones of potential, but the directions are not explicit enough. Two aspects I personally noticed to be an issue where, creating the cheese and the final cook-time in the oven. I found that the soymilk is a necessity in creating a "cheesy" consistence, and the oven cook time is better at 45 minutes. Also, after topping the dish with breadcrumbs, I followed by drizzling olive oil over the entire mixture, and finished it by sprinkling rock salt over top. Finally, in the last few minutes remaining of the oven cook-time, I removed the lid to allow the breadcrumbs to crisp.